<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>变量与常量</title>
</head>
<body>
    <script>
        var a = 10;
        var b=3.14;
        var c= '你好';
        var d=true;
        console.log(a,b,c,d);
        //typeof查看变量类型
        console.log(typeof a,typeof b,typeof c,typeof d);

        var a =6.6;
        console.log(a,typeof a);
        a=false;
        console.log(a,typeof a);
        var a='哈你妈了个头'
        console.log(a,typeof a);

        let x=1;
        console.log(x,typeof x);
        x=6.6;
        console.log(x,typeof x);
        //let x=true;
        //使用let不可以重复声明，会报错
        //console.log(x,typeof x)
    </script>
</body>
</html>